Today, people may access networks and other computer systems from remote locations. Currently available remote access techniques allow users to access their home computer while they are at work or some other remote location. A problem may exist, however, when an individual tries to access a computer within an internal company network such as a local area network (LAN) or an Intranet. For instance, travelling professionals may need to access a file or an application located on their work computer to prepare for a meeting held miles away from their office, or an employee working from home may be in need of certain information stored on his or her computer at work.
Some existing software products provide remote access capability to users wishing to access an internal network computer if all computers within the internal network have public Internet addresses allocated by an Internet Service Provider (ISP). Problems arise when an organization deploys a firewall at the boundary of the internal network to protect it from external access.
A firewall is a device that links an organization's internal network to the Internet and restricts the types of traffic that can pass through, thereby providing security. The firewall may force all network connections to pass through a gateway, where they can be examined and evaluated. The firewall may be configured to use the network address translation (NAT) technique which provides for replacing the source Internet addresses of transactions coming from computers behind the firewall with the Internet address of the firewall itself. As a result, resources on the Internet only see the address of the firewall and cannot learn anything about the addressing structure on the secure side of the firewall. Because all computers behind the same firewall are represented by the same Internet address (i.e. the Internet address of the firewall), a particular computer cannot be identified by a resource outside of the firewall and, therefore, cannot be activated and/or accessed by a remote user. The firewall may also include an application proxy, such as an http proxy that further isolates the enterprise network from the Internet.
Therefore, what is needed is a technique for activating and/or accessing a computer behind a firewall from a remote location in a secure manner.